Pol Lt Suriya Kuadam, a duty officer at Bannang Sata police station, said the incident occurred at 8.33pm at a house in Village Group 1 in tambon Khuan Banglang which was opened as a grocery shop.
At the time two men arrived on a motorcycle at the shop, which had been closed, pretending to be wanting to buy something. When shop owner Jaraporn Wattanasuebtham opened the shop, one of the two men shot her with a handgun in the head, killing her instantly.
The assailants fled after the attack.
Police were investigating.